Investigating tuberculosis by engineering human granulomas

Aims

This research aims to develop a 3D in vitro model of tuberculosis granuloma formation, replacing the need for some studies in animal models.

Background

Tuberculosis (TB) remains a global health pandemic, killing almost two million people per year worldwide. It is caused by various strains of mycobacteria, usually Mycobacterium tuberculosis and is increasingly resistant to current treatments. Tuberculosis research relies heavily on the use of animal models, to both study disease mechanisms and new treatments. No current model accurately reflects disease in man.

A key pathological feature of TB infection is the formation of granulomas in the lungs - nodules where macrophages ‘wall off’ the infection. A novel in vitro granuloma model of TB infection, using human cells and extracellular matrix components, would permit the study of complex in vivo events, potentially better reflecting human disease and replacing the need for some animal studies.

Research details and methods

Using bioelectrospray technology, spheroids will be generated which incorporate primary human cells, Mycobacterium tuberculosis and extracellular matrix components. A number of parameters will be investigated to determine their effect on the host response to infection, including different mycobacterial strains and cells from patients with TB. The spheroids will subsequently be developed as a potential platform for anti-mycobacterial drug screening, potentially further replacing the use of animals.

Tuberculosis (TB) remains a global health pandemic but treatment has remained unchanged for over 30 years. TB research relies extensively on animal studies, including mice, guinea pigs, rabbits and non-human primates, but no model accurately reflects disease in man. We have recently identified matrix metalloproteinases (MMPs) as critical drives of immunopathology in TB and have shown that matrix destruction is a key step leading to TB immunopathology. In this fellowship, I will develop an in vitro granuloma model of TB infection by exploiting bioelectrospray technology to generate spheroids incorporating primary human cells, Mycobacterium tuberculosis (Mtb) and extracellular matrix components.

I will determine the effect of different spheroid matrix composition on granuloma formation and MMP and cytokine production. Next, I will investigate regulation of intracellular signalling pathways and mycobacterial growth by the extracellular matrix, and incorporate divergent Mtb lineages and cells from patients with TB. Finally, I will develop the model to screen for new antimycobacterial compounds active within a granuloma and also to assess efficacy of vaccination strategies ex vivo from patients. These studies will dissect TB immunopathology in an entirely novel in vitro system to identify new therapeutic candidates and evaluate vaccine responses, replacing the need for extensive studies in sub-optimal animal models. The 3D cell culture platform will also be applicable to other human diseases where cell-cell and cell-matrix interactions are important, and so has the potential to replace animal modelling in a wide range of diseases.

Bielecka MK et al. (2017). A Bioengineered Three-Dimensional Cell Culture Platform Integrated with Microfluidics To Address Antimicrobial Resistance in Tuberculosis. mBio 8(1). doi: 10.1128/mBio.02073-16

Tezera LB et al. (2017). Bioelectrospray methodology for dissection of the host-pathogen interaction in human tuberculosis. Bio Protoc. 7(14): pii: e2418 doi: 10.21769/BioProtoc.2418

Tezera LB et al. (2017). Dissection of the host-pathogen interaction in human tuberculosis using a bioengineered 3-dimensional model. eLife 6:e21283 doi: 10.7554/eLife.21283

Walker NF et al. (2017). Matrix Degradation in Human Immunodeficiency Virus Type 1-Associated Tuberculosis and Tuberculosis Immune Reconstitution Inflammatory Syndrome: A Prospective Observational Study. Clinical Infectious Diseases 65(1):121-132. doi: 10.1093/cid/cix231

Al Shammari B et al. (2015). The extracellular matrix regulates granuloma necrosis in tuberculosis. J Infect Dis 212(3):463-73. doi: 10.1093/infdis/jiv076 

Back to top
Pilot study grant

Status:

Closed

Principal investigator

Dr Liku Tezera

Institution

University of Southampton

Grant reference number

NC/L001039/1

Award date:

Jul 2013 - Dec 2014

Grant amount

£74,450